1. Field of the Invention
The present invention relates to a foldable letter that can be mailed, and includes a sheet of paper having an essentially square basic shape within which, on both sides, appears a rectangular field that is of such a size, and that is disposed non-symmetrically and at an angle relative to the square in such a way, that the corners of the rectangle inscribed in the square are spaced from the edges or sides of the square; at those locations where the corners of the rectangle are near the sides of the square, triangular notches are provided, with the most indented point of each notch coinciding with a corner of the rectangle; the four sides of the rectangle each form both a folding line and a base of a triangular closure flap; after the closure flaps have been folded over to one side, the foldable letter can be sealed as a rectangular letter, with strips having an adhesive, such as glue, being provided on one side to secure the closure flaps.
2. Description of the Prior Art
French Patent No. 12 38 882 discloses a packaging sheet in the form of an envelope for particularly valuable journals. This packaging sheet has the features previously described but is not a letter in the normal sense of this word. Thus, this packaging sheet does not involve a sheet that can carry a message, but rather involves wrapping paper for the journal, and is thrown away after the journal is unwrapped. Securing of the closure flaps, and hence sealing of the wrapping, is effected by a separate adhesive strip. As a result, this packaging sheet, even if it were to involve an envelope, would not be suitable for ensuring secrecy of the mail.
A similar-type foldable letter is disclosed in British Patent No. 553 816. This letter starts with a rectangular basic shape in which is also non-symmetrically disposed a rectangular field which results by folding-over external surface parts of the basic shape in a very specific sequence, and which determines the later shape of the sealed letter. However, in contrast to a conventional envelope, this folding-over does not involve independent triangular portions. Rather, the folding of the surface parts in each case also includes regions of the adjacent surface parts, so that the surface parts are of double thickness in certain regions. The gluing does not involve strips located near the edges; rather, a central closure is utilized that cannot assure the secrecy of the mail.
A similar situation is involved with the subject matter of published French application No. 22 89 404, although here, too, a square basic shape having a symmetrically inscribed square for the message can be provided. Sealing of this foldable letter is effected with a plurality of separate strips.
U.S. Pat. No. 960,384 Norman dated Jun. 7, 1910 discloses an envelope having triple, parallel folding lines that extend all the way around; integrally formed-on folding parts are provided at the corners. Due to the presence of triple folding lines, there results a variable packaging thickness of the envelope. However, this brings about a complicated folding process that must be carried out very carefully if a clean exterior appearance of the letter is to be achieved.
Finally, also known are variously reinforced envelopes, and envelopes having carbon paper glued to the inside (German Gebrauchsmusters Nos. 17 37 655 and 82 23 478). For the sake of completeness, though not in any detail, reference is also made to the well-known, so-called air letters (light weight air mail letters) and the customary two-part letters that comprise a sheet of writing paper and an envelope.
The present invention is concerned with the problem of transmitting communications between people. This includes communication via other than the spoken word, especially the written word, but also, for example, a combination of written and pictorial combination. The requirement for communication basically includes all so-called interaction areas, in other words, not just private communications, but also all other communications, including business communications. Even today, the personal writing style of a person can have an important effect; with regard to personal letters, this is even more true when using one's own handwriting. Confronting such personal communication is the increasing use of such communication means where, for reasons of economy, such individual communications are completely, or at least to a large extent, dispensed with. Examples include electronic communication transmitting devices that demand abbreviated language, or even produce an artificial language which is then uniform for all users. It is a concern of the present invention to take steps against this development, which has negative effects on any kind of individuality; one contribution to this cause can be the promotion of the writing and transmitting of letters.